Ancestral lineage and Śrāddh

सङ्करो नरकायैव कुलघ्नानां कुलस्य च । 

पतन्ति पितरो ह्येषां लुप्तपिण्डोदकक्रियाः ।।

- श्रीमद्भगवद्गीता

saṅkaro narakāyaiva kulaghnānāṃ kulasya ca । 

patanti pitaro hyeṣāṃ luptapiṇḍodakakriyāḥ ।।

- Srimad Bhagavadgita

Purport: When there is increase of unwanted population, a hellish situation is created both for the family and for those who destroy the family tradition. In such corrupt families, there is no offering of oblations of food and water to the ancestors.

Due to the non-performance of rituals like pinda Śrāddh and offering water to deceased ancestors etc, the ancestors of such people (who do not perform Śrāddh) have to reside in the lower gross energy planes.  This results in stagnation and erosion of the descendants.

Performing Śrāddh is a part of obeying Dharma, as per science of Sanatana Dharma. Just as there is biological pedigree of transmission of DNA along the family line, there is also a spiritual pedigree. Your departed ancestors can help solve all your problems during this event. Tarpanam works with your Soul DNA. It cleanses the biological and soul desires you have inherited from your ancestral lineage going back 7 generations.  Pitru Paksha emphasises the fact that the ancestors and the current generation and their next unborn generation are connected by blood ties.   The current generation repays their debt to the ancestors in the Pitru Paksha. Maximum aspects are contributed by the immediately preceding 3 generation of ancestors and that is why pinda pradhan is given on their names.

Ancestral lineage of 7 generations

Human DNA has 84 aspects of which 28 are from the food intake by one's parents. 

Remaining 56 aspects got from his immediately preceding 3 generation of ancestors of which 46 aspects as follows: 

• 21 aspects from his father,
• 15 aspects from grandfather and 
• 10 aspects from great grandfather. 

Remaining 10 aspects are as follows:

• 6 from immediately preceding 4th generation, 
• 3 from immediately preceding 5th generation and 
• 1 from immediately preceding 6th generation ancestors.

According to the rules and regulations of fruitive activities, there is a need to offer periodical food and water to the forefathers of the family. This offering is performed by worship of Viṣṇu, because eating the remnants of food offered to Viṣṇu can deliver one from all kinds of sinful actions. Sometimes the forefathers may be suffering from various types of sinful reactions, and sometimes some of them cannot even acquire a gross material body and are forced to remain in subtle bodies as ghosts. Thus, when remnants of prasādam food are offered to forefathers by descendants, the forefathers are released from ghostly or other kinds of miserable life. Such help rendered to forefathers is a family tradition, and those who are not in devotional life are required to perform such rituals. One who is engaged in the devotional life is not required to perform such actions. Simply by performing devotional service, one can deliver hundreds and thousands of forefathers from all kinds of misery. It is stated in the Bhāgavatam:

देवर्षि-भूताप्त-नृणां पितॄणां न किङ्करो नायम् ऋणी च राजन्

सर्वात्मना यः शरणं शरण्यं गतो मुकुन्दं परिहृत्य कर्तम्

स्व-पाद-मूलं भजतः प्रियस्य त्यक्तान्य-भावस्य हरिः परेशः

विकर्म यच् चोत्पतितं कथञ्चिद् धुनोति सर्वं हृदि सन्निविष्टः

- श्रीमद्भागवतं

devarṣi-bhūtāpta-nṛnāṁ pitṝṇāṁ

na kiṅkaro nāyamṛṇī ca rājan

sarvātmanā yaḥ śaraṇaṁ śar yaṁ

gato mukundaṁ parihṛtya kartam

- Srimad Bhagavatam

Purport: “Anyone who has taken shelter of the lotus feet of Mukunda, the giver of liberation, giving up all kinds of obligation, and has taken to the path in all seriousness, owes neither duties nor obligations to the demigods, sages, general living entities, family members, humankind or forefathers.” Such obligations are automatically fulfilled by performance of devotional service to the Supreme Personality of Godhead.

Collated from: bhagavata.org, krishnakatha.in, sanskritdocuments.org